2,113 research outputs found
Vortices and the mixed state of ultrathin Bi films
Current-voltage (I-V) characteristics of quench condensed, superconducting,
ultrathin Bi films in a magnetic field are reported. These show hysteresis for
all films, grown both with and without thin Ge underlayers. Films on Ge
underlayers, close to superconductor-insulator transition, show a peak in the
critical current, indicating a structural transformation of the vortex solid.
These underlayers, used to make the films more homogeneous, are found to be
more effective in pinning the vortices. The upper critical fields () of
these films are determined from the resistive transitions in perpendicular
magnetic field. The temperature dependence of the upper critical field is found
to differ significantly from Ginzburg-Landau theory, after modifications for
disorder.Comment: Submitted to LT23 Proceeding
Convective Term and Transversely Driven Charge-Density Waves
We derive the convective terms in the damping which determine the structure
of the moving charge-density wave (CDW), and study the effect of a current
flowing transverse to conducting chains on the CDW dynamics along the chains.
In contrast to a recent prediction we find that the effect is orders of
magnitude smaller, and that contributions from transverse currents of electron-
and hole-like quasiparticles to the force exerted on the CDW along the chains
act in the opposite directions. We discuss recent experimental verification of
the effect and demonstrate experimentally that geometry effects might mimic the
transverse current effect.Comment: RevTeX, 9 pages, 1 figure, accepted for publications in PR
The Effect of Addition of Lucerne Biomass and NPN Substances on Quality of Grape Pomace Silage
Grape pomace (GP) of white varieties without stalks was ensiled by the method of single factor trial in the two treatments: in the first treatment, with the addition of lucerne biomass (L) of the last cut, which was harvested at the stage of forming pods with equal shares in the weight ratio and in the second with the addition of Benural S (B) in the amount of 1%. Chemical analyses were conducted on GP and L to determine the suitability of biomass for silage and to determine the chemical composition and nutritional value and the process of lactic acid fermentation. It has been found that the biomass of GP had 2 times higher concentration of water-soluble carbohydrates (WSC 140.5:69.4 gkg-1DM) relative to L, and a lower buffer capacity (BC) what makes it 10 times more favourable for ensiling (ratio WSC/BC 13.1 : 1.3). GP, as compared to L, had lower contents of CP, CF, and a lower nutritional value expressed in NEL and NEM units and a higher content of crude fat. Silage with the equal share of GP + L compared to silage with GP + B had a slightly lower CF and significantly less crude fat and ash, especially Ca. More favourable ratio Ca : P (2.93 : 1) was established in silage GP + L compared to 10.1:1 silage GP + B. Silages GP + L in the fermentation process were scored/rated one class higher according to the DLG and Zelter assessment methods, compared to the silages GP + B.
The aim of the study was to investigate the possibility of ensiling grape pomace with equal proportion of biomass of lucerne and added NPN substances and to determine the detailed chemical composition, nutritive value and silage quality on the basis of the process of lactic acid fermentation
Fabrication of One-Dimensional Programmable-Height Nanostructures via Dynamic Stencil Deposition
Dynamic stencil deposition (DSD) techniques offer a variety of fabrication
advantages not possible with traditional lithographic processing, such as the
the ability to directly deposit nanostructures with programmable height
profiles. However, DSD systems have not enjoyed widespread usage due to their
complexity. We demonstrate a simple, low-profile, portable, one-dimensional
nanotranslation system that facilitates access to nanoscale DSD abilities.
Furthermore we show a variety of fabricated programmable-height nanostructures,
including parallel arrays of such structures, and suggest other applications
that exploit the unique capabilities of DSD fabrication methods.Comment: 6 pages, 5 figure
PRODUCTIVE AND TECHNOLOGICAL CHARACTERISTICS OF TABLE VARIETIES GROWE IN THE CONDITIONS OF OPLENAC VINEYARDS
Investigations were carried out in vineyard of King Petar I Karadjordjevic Foundation of at Oplenac. In experiment were tested four table grapes varieties: Black Magic, Victoria, Michel palieri and Muscat Hamburg. Training system is characterized with height of 90 cm on which Guyot pruning is used. In research is studied vegetative potential, fertility, mechanical composition of grape and berries and sugar content and acidity. In red varieties is determined anthocyanins concentration. Michel palieri was with the largest vegetative potential expressed through shoot mass (0,590 kg/vine). The highest values of fertility parameters (number productive shoots, number of inflorescences on spur and arc, coefficients of fertility) had a variety Muscat Hamburg. The highest sugar content was determined in Muscat Hamburg must, a total acid in Victoria variety must. According to anthocyanins Mikele palieri content variety is dissociate (0.179 mg/g fresh weight)
Business-to-business open innovation: COVID-19 lessons for small and medium-sized enterprises from emerging markets
Small and medium-sized enterprises (SMEs) from emerging markets are the most vulnerable types of firms, especially in times of crisis due to time and resource constraints. Thus, this paper aims to help SMEs from emerging markets in choosing the right business partners with whom to cooperate to develop relevant innovations in crisis periods in general, and during the COVID-19 pandemic in particular. To obtain relevant insights, qualitative data from SMEs in Bosnia and Herzegovina were collected in March-April 2020. The findings show that SMEs have embraced new collaborations with business customers and competitors, and developed a collaborative mindset opposed to the traditionally competitive way of doing business in emerging markets. Based on the findings, this paper presents a set of recommendations for managers, and suggests several future research opportunities around the management of openness in the context of SMEs from emerging markets
The Field-Tuned Superconductor-Insulator Transition with and without Current Bias
The magnetic-field-tuned superconductor-insulator transition has been studied
in ultrathin Beryllium films quench-condensed near 20 K. In the zero-current
limit, a finite-size scaling analysis yields the scaling exponent product vz =
1.35 +/- 0.10 and a critical sheet resistance R_{c} of about 1.2R_{Q}, with
R_{Q} = h/4e^{2}. However, in the presence of dc bias currents that are smaller
than the zero-field critical currents, vz becomes 0.75 +/- 0.10. This new set
of exponents suggests that the field-tuned transitions with and without dc bias
currents belong to different universality classes.Comment: RevTex 4 pages, 4 figures, and 1 table minor change
Biological Indication of Heavy Metal Pollution in the Areas of Donje Vlase and Cerje (Southeastern Serbia) Using Epiphytic Lichens
The performance of two epiphytic lichen species (Evernia prunastri (L.) Ach. and Parmelia sulcata Taylor) as bioindicators of heavy metal pollution in natural areas around the city of Nis (southeastern Serbia) were evaluated. The concentration of 19 heavy metals in lichen samples was measured by inductively coupled plasma-optical emission spectroscopy. For the majority of the elements the concentrations found in Parmelia sulcata Taylor were higher than in Evernia prunastri (L.) Ach. In addition, interspecific differences in heavy metal accumulation between Evernia prunastri (L.) Ach. and Parmelia sulcata Taylor are observed. Parmelia sulcata Taylor showed a tendency to accumulate Fe, Mn, Ni and Ti while Evernia prunastri (L.) Ach. preferentially concentrated Cu on both locations. A clear distinction between lithogenic (Mn-Cu-Ti) and atmospheric elements (Ni-Co-Cr-Ag-Pb-Hg) was achieved by cluster analysis
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